Temperature conditioner



United States Patent Inventor Benedict John Cabot Binghamton, NY.

Appl. No. 825,089

Filed April 7, I969 Continuationin-part of Ser. No. v

, 648,753, June 26, 1967, abandoned.

Patented Sept. 29, 1970 Assignee Cabot Industrial Developments, Inc.,

Wichita, Kans.

TEMPERATURE CONDITIONER 8 Claims, 9 Drawing Figs.

US. Cl. 165/65,

165/122 Int. Cl F25b 29/00 Field of Search 165/1, 2,

[56] References Cited UNITED STATES PATENTS 1,565,795 12/1925 Coffey 62/86 Primary ExaminerCharles Sukalo Attorney- Littlepage, Quaintance, Wray and Aisenberg ABSTRACT: Temperature of an ambient fluid is changed by producing a high heat in a heating chamber which is entirely closed except for a single opening into a converging nozzle of a venturi. A throat portion of the venturi is connected to a diverging nozzle, the open end of which is connected to a flow chamber into which ambient fluid is admitted. Flow circulating apparatus, such as a fan, is used in conjunction with a flow chamber to promote flow of the ambient fluid. The heating chamber and the converging portion of the venturi are insulated so that heat is concentrated inwardly. ln a preferred form of the invention, an impeller is provided at the throat of the venturi, and in another preferred form of the invention, the throat is formed as a chambered rotating shaft.

Patented Sept. 29, 1970 3,530,931

Sh,eet l of4 INVLNTOR. BENEDICT-JOHN CABOT f- ATTOR NE YS Patented Sept. 29, 1970 swap/cf JOHN CABOT i BY 5M, Mam

ATTORNEYS Patented Sept. 29, 1970 3,530,931

Sheet of4 BENEDICT J. CABOT 0 5%? a e, ambiance, 0/0 IQ St/JZ/ 5 if j ATTORN EYS E rsRAw QN T QNE This is a continuation-in-part of U.S. Pat. application Ser. No. 648,753, filed June 26, 1967, by Benedict John Cabot for Temperature Conditioner, and now abandoned.

BACKGROUND OF THE INVENTION The need for temperature conditioners which are coolers or heaters of ambient fluids is well known. The need for improved temperature conditioners for controlling temperatures of air is widely recognized. When the amount of heat that is used for changing environmental conditions in order to make an environment more suitable for human occupation or for product manufacture or operation is considered, it is immediately recognizable that even small improvements in the size or efficiency of heaters or coolers represent large gains in saved space or saved energy.

As the population increases and as maintenance and construction costs increase, the demand becomes greater for the providing of small economically operated units which are especially suited for the air conditioning which includes both cooling and heating of spaces upon operational instructions from automatic temperature responsive equipement.

The trend is toward smaller and smaller air conditioning and furnace equipment rooms in houses and in smaller heat exchange devices in offices and industrial buildings.

All devices now in use must dump an unwanted quantity of heat or must absorb an unnecessary amount of heat from a surrounding. Therefore, it is necessary to position such devices so that they communicate with the outside as well as with the confined space in which a temperature change is desired. A need also exists to heat or cool individual spaces without relation to adjacent spaces which may have unique heating or cooling requirements. lt is even possible in one regard that one space may require heating while a nearby space requires cooling. Moreover, it is highly desirable that any device which meets the foregoing needs be portable so that it may be carried from place to place and set in operation simplyby plugging an apparatus into a conventional electric outlet. Thus, a need for a temperature conditioner which is at once small in size in comparison to the place to be cooled or heated, versatile in that it may heat or cool a place and that it may change from cooling mode to heating mode or vice versa very rapidly according to control instructions, that may be positioned at any place within a structure without regard to-the provision of connections to outside for dumping unwantedquantities and which is portable and operative simply by plugging in to a conventional outlet. Moreover, any such deviceshould operate without producing fumes and should offer relatively noiseless operation.

Heat pumps have been widely recognized as convenient sources of cooling and heating which may be readily converted from one mode of operation to the other mode. lnherent in construction of heat pumps is the requirement that the heat pump be located in an exterior wall of a building or have communication duets with the exterior wall ofa building sothat the unwanted quantity, be it excess heat or excess cold, can readily be removed from the space. In short, the heat pump must have a sump, preferably the outside air for dumping excess heat when it is cooling a space or for absorbing heat when it is heating a space. Heat pumps require compressors which in turn require the use of gas fires which produce fumes or electromechanical apparatus which often is associated with noise. Because of their nature, heat pumps are usuallypermanently installed, and cannot be conveniently transported and used in spaces without installation steps which require at a minimum the connection to external heat absorbing or supplying surroundings. Thus, in the true sense, heat pumps are not portable and are not suitable for use simply by plugging in to conventional sources of electrical power.

Two devices which are used to change temperature of air and in which the flow of high pressure gas within a tube is carefully controlled are known in the art. Both methods are basically similar in that high pressure air is delivered to the center of the tube. Both devices deliver cold air from one end of the tube.

A Hilsch vortex tube comprises a very long tube sealed at one end an open at the adjacent opposite end. High pressure air is forced into the tube at the center of the tube. Thereupon, when the tube reaches operating conditions, the sealed end of the tube becomes very hot and the open end of the tube becomes very cold, and cold air issues from the open end of the tube. Thus, in the Hilsch tube high pressure air is admitted in the center of the tube, and reactive flow of air within a tube produces a flow of cold air from one open end of the tube.

Another known form of temperature affecting tube is the Ranque tube. Gas under pressure is admitted through the tangential opening in the center of the tube, so that the flow of the input gas continues through the tube toward one end thereof in a helical sheet-like manner. Axial orifices are provided at either end of the chamber or tube, one of the orifices toward which the liquid or fluid is directed having a cross section smaller than a cross section of a fluid sheet moving toward that orifice so that a portion of the fluid sheet is driven back towards the opposite orifice in such a manner that it is caused to flow over the sheet. The fluid admitted under pressure is guided so as to give it a helical motion toward the first orifice. The cross section of that orifice is restricted, forcing part of the sheet back in the other direction. This produces two sheets of fluids having opposite axial motions. The inner sheet expands and compresses the outer sheet by centrifugal motion, thus applying heat to the outer sheet. A portion of hot fluid passes through the first orifice and through the second orifice there passes a relatively cool fluid. The relatively cool fluid may be volumetrically augmented by ambient air flowing inwardly and then outwardly through the second orifice, first being drawn inward by the reduced pressure in the central zone of the tube and then being forced outwardly by the gymtory currents. Operation of the Ranque tube is described more fully in U.S. Pat. No. 1952,28], issued Mar. 27, i934, for Method and Apparatus for Obtaining From a Fluid Under Pressure Two Currents of Fluids at Different Temperatures by Georges Joseph Ranque.

Both the Ranque tube and the Hilsch tube require inputs of air under high pressure. Thus, both of those temperature effecting tubes require the use of compressors to provide the compressed air in inputs. Both devices require means to dump the unwanted heat quantity. When cooling is desired of the tubes, means must be provided to dispose of the heat removed by the tubes. When heating is required of the tubes, means must be provided to dispose of the temperature-reduced air generated by the tubes. Thus, in the true sense, the temperature affecting tubes of Hilsch and Ranque are not portable and are not suitable for use simply by plugging the tubes into a conventional source of electrical power. Both tubes require special installation procedures for the heat dumping requirements.

Notwithstanding the wide use of heat pumps and related devices which are small reversible to provide either cooling or heating, of temperature affecting tubes such as the Hilsch and Ranque tubes, the need for small versatile and dependable apparatus which may be set into operation simply plugging into conventional sources of electrical energy and which requires no special installation procedures continues as the well established problem for which heretofore there has been no satisfactory solution.

SUMMARY OF THE INVENTION the device is connected to a heating element to provide heat and light energy in a sealed and insulated chamber. The input is also connected to impellers and fans which provide effective and notwithstanding the long knowledge in existence distribution and circulation of energy and ambient fluids upon which temperature change is desired.

The invention herein disclosed is a temperature conditioner which uses power input to produce heat and light energy and which employs that energy in the changing of temperature of a fluid mass. Apparatus for carrying out the broad objectives of this invention comprises a sealed chamber in which are disposed one or more heating elements. The heating elements are connected to a power source for conversion of the power into heat and light energy within the sealed chamber. The chamber is completely surrounded by insulation so that all heat energy generated within the chamber is reflected inwardly back into the chamber. Chamber opens into the divergent portion of a converging nozzle. The narrowest dimension of which is relatively small as compared to a chamber cross section. The small end of the converging nozzle communicates with a small end of a diverging nozzle. The large end of the diverging nozzle is connected to a chamber in which ambient fluid if circulated. Thus, energy which is generated within the sealed chamber is directed through the converging and diverging nozzles into contact with ambient fluid circulated in the outer chamber. A fan which is connected to the latter chamber circulates the fluid therein.

In a preferred form of the invention, a high speed motor having a high speed rotor is mounted between the converging and diverging nozzles so that the small ends of the nozzles communicate via the high speed impeller of the motor. In one embodiment, the high speed rotor between the small ends of the nozzles is formed as an internally chambered shaft. Ends of the shaft have restricted openings which are commensurate with the small openings of the diverging and converging nozzle portions. The plural cylindrical chambers within the shaft are communicated with similar sized axial openings between chambers. Chambers are inwardly stepped so that the innermost chambers have the smallest radial and volumetric dimensions.

In another form of the invention, a high speed impeller forms the rotor of the high speed motor. Preferably, the impeller is mounted without bearings so that the impeller is suspended magnetically and by buildup of tiny particles between the shrouded blade and its stationary cylindrical casing. Such a bearing in which surfaces are spaced from each other so that there is no frictional contact are generally referred to as air bearings or more particularly in this case molecular or ion bearings.

While an understanding of the interior workings and the heat and energy exchange which results in the cooling of ambient fluids is not necessary to the understanding of the invention, it is apparent that the convergent nozzle portion and the insulation around the entire remaining sealed chamber is effective to focus and concentrate the heat and light energy produced by the elements within the sealed chamber into the restricted opening of the chamber. Ambient fluid, for example air, which if forced through a second outer chamber in an axial direction away from the diverging nozzle or which is cir culated in the chamber, flows outwardly along the wall of the chamber. A relatively low pressure area is developed centrally in the outer chamber and in the diverging nozzle portion. Energy is imparted to the ambient fluid and the flow of energy is promoted and controlled by the rotor of the high speed motor and the flow of energy and ambient fluid is controlled by the diverging nozzle and by the outer chamber in such a manner that the energy imparted to the fluid further drives the fluid, expands the fluid and enhances the low pressure in the central area which further expands the fluid with a resulting cooling of the fluid which is circulated outwardly from the outer chamber. Since the heat energy generated in the sealed chamber is thermally insulated from the surroundings and used entirely in the production of temperature change in the ambient fluid, it is not necessary to dump excess heat of the apparatus such as is the case in known temperature affecting devices.

One objective of this invention is the provision of a temperature conditioner which may be employed simply connecting the conditioner to a conventional source of electrical power.

Another objective of this invention is the provision of a temperature conditioner which has a sealed and insulated chamber in which heating elements are disposed, and in which the sealed insulated chamber communicates with a converging nozzle so that energy produced by the heating element and refelected andretained in the chamber will be focused and concentrated in the small end of the converging nozzle, the apparatus further having a rotor spinning at high speed so that heat is passed on to a diverging area to cause the expension of an ambient mass of fluid, cooling the fluid and converting the heat into expansion work on the fluid.

These and other objectives of the invention and particular embodiments of apparatus for attaining the objectives of this invention will be apparent from the disclosure which includes the specification, claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional representation of one apparatus for attaining the objectives of the invention. On the left is a sealed and insulated heating chamber with heating elements disposed therein and on the right is an outer chamber with a fluid-circulating squirrel cage. Centrally located between the convergent and divergent cone is an inductance motor with a rotor formed as a bladed and shrouded impeller.

FIG. 2 is a plan view in which part of the apparatus has been cut away to show in section the heating chamber insulation and heating elements.

FIG. 3 is an enlarged sectional detail of the throat area between the converging and diverging cones and the rotor which is mounted centrally in the throat area and which is mounted and suspended therein through the magnetic field plus molecular or ion bearings for frictionless rotation.

FIG. 4 is a transverse sectional view of the throat area between the converging and diverging nozzles, showing in additional detail the structure of the shrouded rotor blades.

FIG. 5 is a diagrammatical partly cross-sectional view of the impeller, schematically indicating a portion of the induction motor which drives the impeller.

FIG. 6 is a perspective view of an embodiment of the invention which is relatively miniaturized.

FIG. 7 is an exploded view of the embodiment shown in FIG. 6, illustrating in detail elements of that embodiment.

FIG. 8 is a cut away view of an impeller and motor employed in the embodiment of FIGS. 6 and 7.

FIG. 9 is a sectional elevation of the shaft of the induction motor shown in FIG. 8.

DETAILED DESCRIPTION OF THE DRAWINGS 1 designates the apparatus for practicing the method disclosed herein, and consists of a housing 2 having walls 3 spaced from the housing 2, forming a tight enclosure 4 for an electrically operated heating element 5 including (in this case) Calrods 6 from a wire connection 7 to a source of electrical supply (not shown). The enclosure 4 has an offset portion 8 and attached thereto is a tubular member 9 extending therethrough for enclosing the Calrods 6 and the tube 9 is turned at right angles, as indicated at 10, and screw threadedly connected at 11 to a converging portion 12 of the inductance motor 13, which in turn has its other end screw threadedly connected as at 14 to the inductance motor also screw threadedly connected at 16 to a diverging portion 17 of the inductance motor 13, having its other end screw threadedly attached at 18 to a tubular member 19 connecting with a second housing 19', as shown in FIG. 1, which directs the energy downwardly into a compartment 20, which houses the squir rel-cage 21 operated by a motor 22 through an electrical inlet 23 from a source of supply (not shown).

A wall 24 is spaced from the wall 3 of the heating element 5, and is connected to a horizontal wall 25 which in turn forms a portion of the wall 26 to which the tubular member 19 is attached as previously stated. The walls 3 and 34 and 25 and the top wall 27 are all spaced from the heating unit and the tubular member through which the heat is cooled and require insulation as indicated at 28, and which may be of any suitable insulating material, but here shown to be rock wool. Plastic or other material may be utilized.

The tubular portion or throat of the inductance motor is illustrated in FIG. 3 and the inside 29 of the inductance motor is provided with an annular groove 30 in which is adapted to rotate an impeller 31 having blades 32. The impeller includes on its outer rim four cylindrical type magnets 33 evenly spaced for proper commutation at high speed.

35 indicates the stator, preferably of soft magnetic material having a winding positioned to receive the magnet at the time it reaches commutation and maximum velocity. It will be noted the stator thickness is equal to the diameter of the magnet. 36 indicates a tapped winding resistor included in the circuit and a coil-form terminal to mount the resistors and transistors 38 as a complete assembled circuit board.

When the impeller magnets 33 enter the stator, the transistor will remain in its normal cutoff or open circuit position. During this entry period, the attraction force of the permanent magnet will act upon the stator to impart energy to the balanced impeller. The speed of the impeller increases and the magnet will begin to leave the stator, energizing or generating a polarity to start regeneration processes to trigger the transistor to full conduction. The triggering process occurs in less than 0.0002 seconds. Flow of current through the transistor and part of the winding will produce a mangetic field which repels the balance magnet away from the stator poles. The driving forces of attraction and repulsion are designed to deliver equal amounts of energy so that the natural'balance rate of the impeller is not disturbed. Use of the resistor will dampen the circuit, which prevents self-oscillation. The heating element is capable of heating from 0 to 2,000F., and the impeller rotates from 0 to 1.000 k.c. (approximately one million rpm).

in normal procedure, the stator operates the armature for added precision for a free spinning, high velocity balanced wheel. For example using a 1.0 gram wheel, 1.75 cm in diameter driven by an input of 8.0 microwatts at a 5,000 spin rate has a total excursion of 360. The Alnco V magnet 33 measures 1.0 mm in diameter and 60 mm in length. Duration ofelectrical impulses is 0.005 seconds.

ln-Fig. 5, the operation is a simple a.c. to d.c. generation amplification in which the energy build-up of the armature and electrodes act as brushes. The field is an externally generated uniform parallel magnetic field, and movement ofa conductor at right angles through the magnetic field produces a voltage in a plane mutually perpendicular to the field and to the direction of movement. As the volumetric (mass) energy rate is dependent solely on energy build-up, the induced voltage is also directly proportional to the volumetric energy rate. The ions are trapped in the housing of the impeller section, this allows the impeller to ride on an ion bearing while being suspended in the magnetic'field during high and low speeds.

The magnetic field principle is used primarily to rotate the impeller and to suspend the impeller in the inductance motor without the necessity of bearings or any other physical tie down. Speeds of the impeller are dependent upon the rheostat application plus applied circuitry.

in a preferred form, the apparatus shown in HQ. 6 has an overall dimension of approximately 24 inches by 5 inches by 7% inches. Numeral 40 generally represents the entire temperature conditioner apparatus shown in FIG. 6. The temperature conditioner 40 is constructed of a series of modular elements joined together by interfitting end portions and held compressively together by end blocks 42 and 44 and four cooperating bolts 46. The first modular element 50 comprises an insulated chamber sealed at the end thereof adjacent block 42. Heating elements are disposed within the chamber 50 and the heating elements may be supplied directly by power from N0 volt a.c. sources. Alternatively, heating elements within chamber 50 may be constructed to operate on 12 volts which may be supplied from a 110 volt source connected through transformer 52. In a preferred embodiment of the invention, the apparatus is supplied directly by 12 volt dc. power, in which case transformer 52 is not employed, and the overall length of the apparatus is reduced to 18 inches or thereabouts. Heat and light energy produced in chamber 50 is focused and concentrated centrally by converging cone portion 60. Central section 70 houses an induction motor which drives a high speed impeller further described in detail. The output of section 70 is connected to a diverging conical portion which connects with an outer chamber through which ambient air is drawn by fan 92.

Referring to FIG. 7, heating elements 54 are disposed within heating chamber 50 which is surrounded by insulation 56 to concentrate and reflect the heat energy in the heating tube. A recessed annular groove 58 at the open end of heating chamber 50 receives a corresponding tongue portion 62 of converging cone element 60 for receiving the cone in tight sealing arrangement. The sloped face 64 of conical element 60 describes a relatively large angle with an axis of the tube-like assembly, for example about 6575. Whereas the diameter of the assembly is roughly 3 inches, the overall length of the conical element 60 is a fraction of an inch. A tongue 66 is pro vided in the forward end of the converging conical element 60 to interfit with a cooperating groove in the next adjacent element 70. A central recess 68 which communicates with the smaller end of the conical wall 64 receives a cooperating end 71 of motor shaft 72 in central element 70. Shaft 72 is hollow and the enlarged end 71 fits within recess 68 of conical element 60 so that the small central opening in shaft 72 is exactly positioned at the small end of the converging surface 64.

Central housing 70 houses an induction motor 73 of miniature size. Block 74 connects motor 73 with the outer wall of the housing 70. The motor 73 may be mounted rigidly to block 74, or in a preferred form block 74 is rigidly attached to the outer wall of element 70 and is connected to motor 73 nonrigidly serving a single function of preventing the outer portion of the motor from rotating. Motor 73 is then centered in position by the cooperating enlarged bearing surface ends 71 and 75 of rotor shaft 72. Annular grooves 76 in the outer wall of element 70 receive complementary configured elements 66 and 86 in the adjacent converging and diverging conical modules 60 and 80, respectively. Enlarged shaft end 75 is received within recess 88 of element 80. Elements 80 and 60 may be constructed in a similar manner since the slope of conical face 84 is similar to the slope of conical face 64. in fact, elements 80 and 60 may be interchangeable. A modified form of conical element 80 has a single distinction from the converging conical element 60 and that is that holes may be drilled leading from the outer surface of conical element 80 to the sloping conical surface 84 for drawing ambient air from the external surface into the low pressure area of the cone. The forward edge 82 of element 80 is configured to be received within a corresponding groove 94 in mixing chamber 90. Mixing chamber 90 is provided with a fan at the open end which is remote from conical element 80 for mixing ambient fluid such as air with the heat energy which is provided by the remainder of the apparatus. Mixing chamber 90 may be provided with holes adjacent conical element 80 so that ambient fluid is drawn in through the holes 89 and through holes in the side of the mixing chamber.

As in the other embodiment of the invention, energy is imparted to ambient air at a low the air and causing cooling thereof. When the fan in chamber 90 is driven in the opposite direction, cone 84 becomes a compression area, and energy added to the ambient air in the area of cone 84 and in the rotor, further heats the air causing flow outwardly of heated air.

pressure area further expanding As shown in detail in FIG. 8, motor 73 is constructed as a miniature motor which runs on d.c. power which is controlled by potentiometer control 78 shown in FIG. 6. Higher voltages cause the motor to run at increased speed. The motor housing 70 has axial dimension of approximately 3 inches and diameter of approximately 2 inches. Flat plates 101 are provided at opposite ends of the assembly 70. The outer portions 103 or rotor shaft 72 have an outer diameter of approximately .375 inches. The central portion 105 of shaft 72 has an outer dimension of approximately .750 inches diameter and is approximately .925 inches long between cylindrical magnet elements 107. Windings 108 on laminated cores 109 are controlled in a well-known manner to spin rotor 72 about its axis.

As shown in FIG. 9, rotor shaft 72 is constructed of a series of chambers which are successively volumetrically reduced from outer chambers toward center chambers. A central opening of approximately .l25 inches for about one-eighth of an inch extends through the shaft and through medial disks which separate the shaft into successive chambers. Disks separating the chambers are preferably about .062 inches thick. Outer chambers 111 are approximately .400 inches long. Chambers 113, 115, and 117 are each approximately .125 inches long.

Heat energy produced in chamber 50 and focused in converging cones 60 is transmitted through the first outer chamber 111 where the energy is forced into a vortex motion in the high speed shaft 72. As the energy proceeds through successive decreasing and then increasing chambers and finally into the diverging conical section. During the flow, the heat energy is affected by the vortexes formed in the chambers of the rotating shaft such that vibrations are produced which further act to impart energy on the ambient air, further expanding and cooling air from a reduced pressure area when the fan drives air in a direction away from converging nozzle 80 and further providing heating and compressing energy to the air when the fan drives ambient air in chamber 90 toward the direction of the converging conical member 80.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

I claim:

1. Temperature conditioner apparatus for changing ambient temperatures comprising:

an enclosed heating chamber having only one open end;

heating elements mounted within the heating chamber and spaced from the open end thereof, the heating elements being connected to a source of electrical power;

insulation surrounding the heating chamber for preventing outward flow of heat energy through walls thereof and for concentrating heat energy with the chamber thereby directing heat energy to the open end;

a converging conical element connected to the open end of the heating chamber and tightly fitting therewith, the converging conical element having a wide opening adjacent the heating chamber and a restricted opening at a point remote from the heating chamber;

a throat element connected to the converging conical element, whereby the restricted opening of the converging conical element communicates with the throat element;

a diverging conical element connected to the throat element, the diverging conical element having a restricted opening adjacent the throat element and a relatively large opening spaced from the throat element;

an outer mixing chamber connected to the diverging conical element whereby the larger opening of the diverging conical element communicates with the outer mixing chamber; and

ambient air circulating means disposed in the outer mixing chamber for circulating ambient air in the mixing chamber. 2. The temperature conditioner apparatus of claim 1 wherein the throat portion comprises a housing interconnecting the conical converging and diverging conical elements, and wherein the throat element further comprises a housing, an impeller motor disposed within the housing, the impeller motor having a high speed rotor centrally disposed within the housing and communicant with the smaller openings of the converging and diverging conical elements.

3. Temperature conditioner apparatus of claim 2 wherein the rotor comprises an elongated shaft, blades extending radially outwardly from the center of the shaft and a shroud connecting outer ends of the blades, and wherein the motor further comprises a cylindrical surface slightly spaced outwardly from the shroud.

4. The temperature conditioner apparatus of claim 2 wherein the rotor-comprises a hollow shaft having restricted central openings at opposite ends thereof and having a series of chambers defined within the shaft and separated from each other by a plurality of radial disks with central openings positioned within the shaft and spaced from the ends of the shaft.

5. Temperature conditioner for changing ambient temperatures comprising:

a housing having walls;

a heating element spaced from the housing walls, the space between the heating element and said walls being insulated;

a tube connected to said heating element having one end turned to a horizontal position;

an inductance motor connected to one end of said tube;

a compartment having an opening therein; I

means connecting said compartment through said opening to said inductance motor;

a squirrel cage in said compartment;

a motor for operating said squirrel cage;

an impeller extending transversely of said inductance motor; and

means for rotating said impeller for changing the heat from the heating element to cold air and passing the same to said compartment.

6. The apparatus of claim 5, wherein said inductance motor consists of a converging portion attached to the tube con nected to the heating element and a diverging portion connected to the means connecting the inductance motor to the compartment, a tubular portion between the converging and diverging portions and said impeller is located in said last named tubular portion.

7. The apparatus of claim 6, wherein the means for rotating said impeller includes a set of four magnets on the rim of the impeller, a 4-pole winding to oppose and start said magnet, a stator, a series of resistors, and a series of transistors operable from a source of electric supply.

8. The apparatus of claim 1, wherein said impeller is rotated at above 1,000 r.p.s. 

